Feature/dns protocol (#543)

Added DNS update protocol message

Added sync to clients

Update nameserver API with new fields

Added default NS groups

Added new dns-name flag for the management service append to peer DNS label

management/server/dns.go

@@ -0,0 +1,152 @@
+package server
+
+import (
+	"fmt"
+	"github.com/miekg/dns"
+	nbdns "github.com/netbirdio/netbird/dns"
+	"github.com/netbirdio/netbird/management/proto"
+	log "github.com/sirupsen/logrus"
+	"strconv"
+)
+
+type lookupMap map[string]struct{}
+
+const defaultTTL = 300
+
+func toProtocolDNSConfig(update nbdns.Config) *proto.DNSConfig {
+	protoUpdate := &proto.DNSConfig{ServiceEnable: update.ServiceEnable}
+
+	for _, zone := range update.CustomZones {
+		protoZone := &proto.CustomZone{Domain: zone.Domain}
+		for _, record := range zone.Records {
+			protoZone.Records = append(protoZone.Records, &proto.SimpleRecord{
+				Name:  record.Name,
+				Type:  int64(record.Type),
+				Class: record.Class,
+				TTL:   int64(record.TTL),
+				RData: record.RData,
+			})
+		}
+		protoUpdate.CustomZones = append(protoUpdate.CustomZones, protoZone)
+	}
+
+	for _, nsGroup := range update.NameServerGroups {
+		protoGroup := &proto.NameServerGroup{
+			Primary: nsGroup.Primary,
+			Domains: nsGroup.Domains,
+		}
+		for _, ns := range nsGroup.NameServers {
+			protoNS := &proto.NameServer{
+				IP:     ns.IP.String(),
+				Port:   int64(ns.Port),
+				NSType: int64(ns.NSType),
+			}
+			protoGroup.NameServers = append(protoGroup.NameServers, protoNS)
+		}
+		protoUpdate.NameServerGroups = append(protoUpdate.NameServerGroups, protoGroup)
+	}
+
+	return protoUpdate
+}
+
+func getPeersCustomZone(account *Account, dnsDomain string) nbdns.CustomZone {
+	if dnsDomain == "" {
+		log.Errorf("no dns domain is set, returning empty zone")
+		return nbdns.CustomZone{}
+	}
+
+	customZone := nbdns.CustomZone{
+		Domain: dns.Fqdn(dnsDomain),
+	}
+
+	for _, peer := range account.Peers {
+		if peer.DNSLabel == "" {
+			log.Errorf("found a peer with empty dns label. It was probably caused by a invalid character in its name. Peer Name: %s", peer.Name)
+			continue
+		}
+
+		customZone.Records = append(customZone.Records, nbdns.SimpleRecord{
+			Name:  dns.Fqdn(peer.DNSLabel + "." + dnsDomain),
+			Type:  int(dns.TypeA),
+			Class: nbdns.DefaultClass,
+			TTL:   defaultTTL,
+			RData: peer.IP.String(),
+		})
+	}
+
+	return customZone
+}
+
+func getPeerNSGroups(account *Account, peerID string) []*nbdns.NameServerGroup {
+	groupList := make(lookupMap)
+	for groupID, group := range account.Groups {
+		for _, id := range group.Peers {
+			if id == peerID {
+				groupList[groupID] = struct{}{}
+				break
+			}
+		}
+	}
+
+	var peerNSGroups []*nbdns.NameServerGroup
+
+	for _, nsGroup := range account.NameServerGroups {
+		if !nsGroup.Enabled {
+			continue
+		}
+		for _, gID := range nsGroup.Groups {
+			_, found := groupList[gID]
+			if found {
+				peerNSGroups = append(peerNSGroups, nsGroup.Copy())
+				break
+			}
+		}
+	}
+
+	return peerNSGroups
+}
+
+func addPeerLabelsToAccount(account *Account, peerLabels lookupMap) {
+	for _, peer := range account.Peers {
+		label, err := getPeerHostLabel(peer.Name, peerLabels)
+		if err != nil {
+			log.Errorf("got an error while generating a peer host label. Peer name %s, error: %v. Trying with the peer's meta hostname", peer.Name, err)
+			label, err = getPeerHostLabel(peer.Meta.Hostname, peerLabels)
+			if err != nil {
+				log.Errorf("got another error while generating a peer host label with hostname. Peer hostname %s, error: %v. Skiping", peer.Meta.Hostname, err)
+				continue
+			}
+		}
+		peer.DNSLabel = label
+		peerLabels[label] = struct{}{}
+	}
+}
+
+func getPeerHostLabel(name string, peerLabels lookupMap) (string, error) {
+	label, err := nbdns.GetParsedDomainLabel(name)
+	if err != nil {
+		return "", err
+	}
+
+	uniqueLabel := getUniqueHostLabel(label, peerLabels)
+	if uniqueLabel == "" {
+		return "", fmt.Errorf("couldn't find a unique valid lavel for %s, parsed label %s", name, label)
+	}
+	return uniqueLabel, nil
+}
+
+// getUniqueHostLabel look for a unique host label, and if doesn't find add a suffix up to 999
+func getUniqueHostLabel(name string, peerLabels lookupMap) string {
+	_, found := peerLabels[name]
+	if !found {
+		return name
+	}
+	for i := 1; i < 1000; i++ {
+		nameWithSuffix := name + "-" + strconv.Itoa(i)
+		_, found = peerLabels[nameWithSuffix]
+		if !found {
+			return nameWithSuffix
+		}
+	}
+	return ""
+}